The lap of luxury this is not: Das Park hotel features rooms crafted from 9.5-ton concrete drainage and sewage pipes. Toilets and showers are a short walk from your cylindrical accommodations. Guests looking for a minimalist vacation can request a key code online, then pay what they wish after a maximum stay of three days. But plan ahead: booking is closed until spring of next year.
Payment by donation only, dasparkhotel.net. A second location has also opened near Essen in Germany.